Wikipedia
Notochthamalinae
The subfamily Notochthamalinae Foster and Newman, 1987, was proposed for members of the barnacle family Chthamalidae with elongated scuta and very narrow terga deeply interlocked, sometimes concrescent. Shell plates may become concrescent with age in some species. Soft part characters include card setae on some or all of cirri I to III, and mandible with or without combed lower edge. Poltarukha made further revisions in 1996.